Protective Packaging – A Guide To Moisture Barrier Bags

What Is A Moisture Barrier Bag?

Moisture barrier bags, also known as mbb, heat seal bag, or mylar bag, is a specialized packaging product designed to provide an effective barrier against moisture vapor and other outside contaminates. These bags are commonly used in many industries, including electronics, aerospace and automotive. They protect sensitive components, equipment, and electronics from corrosion caused by moisture vapor. Moisture barrier bags are typically constructed with multiple layers, including a layer of aluminum which forms the main barrier and allows for the lowest water vapor transmission rates in any flexible material. Other substrates such as Polyester, Nylon, Polypropylene and Polyethylene provide strength, flexibility, and additional protection against punctures or tears.

Why Are Moisture Barrier Bags Important To Use? 

These bags offer superior protection against the effects of moisture vapor on sensitive materials and components. When exposed to moisture vapor or oxygen ingress, metals can undergo oxidation, leading to rust, degradation, and ultimately, failure. Electronic components can experience malfunctions, reduced performance, or even complete failure due to the presence of moisture. Additionally, moisture promotes the growth of mold and mildew, which can further damage products and compromise their integrity. By utilizing MBBs, the risk of moisture vapor-related corrosion is significantly reduced. These bags create a controlled atmosphere at lower than 38% relative humidity at which corrosion occurs. The low transmission rate of the material means no further moisture vapor enters the bag, maintaining a dry environment around the packaged items. The high barrier properties of the bags safeguard the contents from high humidity, condensation, and exposure to external sources. This ensures that sensitive materials, electronic components, or high-value equipment remain protected, extending their lifespan and preserving their functionality.

Features & Properties 

Barrier bags possess several key features that make their protection effective against moisture vapor, oxygen and more. 

Moisture Barrier Properties 

The primary feature of these heat seal bags is their ability to create a reliable barrier against moisture vapor and atmospheric gasses. The combination of the multiple laminated layers, including the layer of aluminum, prevents moisture vapor from entering, thus maintaining a dry environment for the enclosed items. 

Strength & Durability

These bags are resistant to punctures and tears, meaning they provide reliable protection during shipment and storage. They withstand various environmental conditions and maintain their barrier properties over time.

The Use Of Desiccant

MBBs are also designed to accommodate the use of desiccants. Desiccants absorb moisture from their surrounding environment, helping to maintain low humidity levels within the protective packaging.

Who Uses Moisture Barrier Bags?

Barrier bags play a crucial role in many industries. Due to the high barrier protection, these bags are a great solution for shipping and storing all of your moisture-sensitive products from EV battery components to large aerospace components.

Electronic Vehicle Industry

With the EV industry booming, the need for protective packaging is on the rise. EV battery components made from Lithium are extremely susceptible to moisture vapor and can cause catastrophic damage if it is introduced to the battery components. The use of barrier foil packaging helps to keep the life of these batteries stable and functional for use.  Want to learn more about barrier foil packaging in the EV industry? Check out how we helped a major EV manufacturer package their battery components here. 

Aerospace Industry 

Moisture barrier bags are utilized for the packaging and storage of critical components, such as avionics, electronic modules, sensors, and more. These components are often susceptible to corrosion, which can compromise their performance and reliability.  Moisture barrier bags provide an effective barrier against humidity, preventing the entry of moisture vapor and ensuring the long-term integrity of the enclosed components. By using moisture barrier bags, aerospace companies can minimize the risk of corrosion-related failures, improve equipment lifespan, and maintain optimal functionality throughout the service life of their aircraft and spacecraft.

How Can We Help You? 

We manufacture custom bags for you and dispatch them to your site with industry-leading lead times, so you know that you will never have to wait for your packaging, leaving your products open to corrosion. Our packaging experts will help support your packaging needs every step of the way. Whether you are packaging small battery components for Electric Vehicles or large turbines and engines for spacecraft, we will find the perfect packaging material and format for your application.